This invention relates to a dust removing system for an optical disk device, and more particularly to a system for cleaning an objective lens of an optical head in an apparatus in which an optical disk device is employed.
As types of optical disk devices, there are optical disk recording and/or reproducing devices, magnetic optical disk recording and/or reproducing devices and so forth. Those optical disk devices perform high density recording and/or reproduction of information on and/or from an optical disk and have a feature that a record medium can be exchanged readily. On the other hand, since those optical disk devices deal with light, a laser beam projected from an objective lens or a laser beam reflected from a disk and focused by an objective lens may possibly be obstructed by dust accumulated from the ambient air during use for a long period of time, which will cause deterioration in performance of the optical disk device such as irregular access.
Meanwhile, frictional resistance at a sliding portion of a bearing for a linear motor for driving an optical head may be increased by use for a long period of time or sliding resistance may be increased by dust, which increases a seek time of the optical head.
Conventionally, such apparatus are known wherein a dust protective wall or a filter is provided for the dustproof object, and an upper face of a lens is cleaned in response to an inserting operation of a disk by means of a brush serving as a manual or automatic dust removing mechanism for the removal of dust while movable parts are lubricated. An exemplary one of apparatus wherein a filter is used for the removal of dust is disclosed in U.S. Pat. No. 4,777,549.
Such conventional apparatus do not take such measures as positive detection against a delay in access time or the like which may arise from dust accumulated on an objective lens. No measures for the protection against dust by positive maintenance are taken either. Further, a method for coping with a case wherein dust cannot be removed even if an upper face of an objective lens is cleaned by a brush is not provided clearly. Further, since a method of lubricating a sliding portion or a method of removing dust is not clearly indicated in detail, much time may be required for a user or a service man to disassemble the device and clean an upper face of an objective lens, or dust cannot be removed. Accordingly, there is a problem that the MTBF (Mean Time Between Failures) is decreased while the MTTR (Mean Time To Repair) is increased, and the availability of the system is deteriorated. Further, there is a problem that the reliability of the system is deteriorated. Also there is a problem that the maintenance property of the system is low.